The Journal of Medical Microbiology, Vol 36, Issue 4 264-268, Copyright © 1992 by Society for General Microbiology
Entero-adherent Escherichia coli is an important diarrhoeagenic agent in infants aged below 6 months in Calcutta, India
A. R. Ghosh, G. B. Nair, T. N. Naik, M. Paul, S. C. Pal and D. Sen
National Institute of Cholera and Enteric Diseases, Calcutta, India.
Escherichia coli adherent to HEp-2 and HeLa cells were isolated from the
faeces of 43 (19.7%) of 218 hospitalised infants aged below 6 months with
acute diarrhoea. No conventional virulence factors, including enterotoxin
production--heat-labile (LT) or heat-stable (ST), the verotoxin (VT) or
shiga-like toxin (SLT)--or the invasive phenotype (determined by the Sereny
test) could be detected among these isolates. Out of the 43 isolates, 16
(37.2%) were of the known enteropathogenic O:K serogroups--enteropathogenic
E. coli (EPEC). The remaining 27 (62.8%) isolates showed different types of
adherence to HEp-2 and HeLa cells which was diffuse (40.7%), localised
(37.0%), or both (22.3%); they were identified as entero-adherent E. coli
(EAEC). The EAEC isolates adhered to HEp-2 and HeLa cells in the presence
of mannose, lactose, fucose, galactose, and fetuin, indicating that
adhesion was not specific for these sugars or glycoprotein.
Haemagglutination and the salt aggregation test (SAT) did not correlate
with patterns of adherence. The results of this study indicate that LA-EAEC
is an important aetiological agent of acute diarrhoea in infants aged below
6 months in Calcutta.
